BACKGROUND
Technical Field
[0001] The disclosure relates to a battery management technology, and in particular relates
to a battery management system and a battery management method.
Description of Related Art
[0002] With the trend of the energy development, storage batteries are widely applied to
application requirements of diverse fields, and how to effectively manage and protect
the use of storage batteries is one of the important researches and development focuses
nowadays. However, the traditional battery management method mostly performs power
management and protection on the single cell only, or only uses a specific battery
connected in series or connected in parallel to monitor the battery, so that the effective
battery management and protection for the battery application field of common high
voltage battery packs cannot be performed.
[0003] In this regard, multiple cells are required for the high voltage battery packs to
be connected in series to increase the terminal voltage of the battery packs to enable
the high voltage battery packs to meet the rated voltage required by the load. Nonetheless,
since there are slight differences between the cells due to internal resistance, thereby
the terminal voltage of each cell is not exactly the same, and the capacity and internal
resistance of each cell may be different. In this way, in the process of the charge
movement of the battery packs during the charge and the discharge period, there is
the possibility to cause the terminal voltage of a certain cell in the battery packs
to exceed or be lower than the threshold voltage, but the traditional battery management
system cannot perform the response based on instantaneous or accurate judgement of
the battery state of each cell. Therefore, the safety and lifetime of the battery
packs are often reduced.
SUMMARY
[0004] The disclosure provides a battery management system and a battery management method,
which can accurately estimate multiple present battery powers of multiple battery
packs.
[0005] A battery management system of the disclosure includes a temperature sampling circuit,
multiple voltage measurement circuits, a current sampling circuit, and a microcontroller.
The temperature sampling circuit is configured to obtain a temperature parameter of
multiple battery packs. The voltage measurement circuits are respectively coupled
to the battery packs and are configured to obtain multiple open circuit voltage parameters
of the battery packs. The current sampling circuit is coupled to the battery packs
and is configured to obtain a current parameter of the battery packs. The microcontroller
is coupled to the voltage measurement circuits, the current sampling circuit, and
the temperature sampling circuit. The microcontroller obtains multiple initial state-of-charge
parameters of the battery packs according to the open circuit voltage parameters and
the temperature parameter and respectively calculates multiple present battery powers
of the battery packs according to the initial state-of-charge parameters, the temperature
parameter, and the current parameter.
[0006] A battery management method of the disclosure includes the following steps: obtaining
a temperature parameter of multiple battery packs through a temperature sampling circuit;
obtaining multiple open circuit voltage parameters of the battery packs through multiple
voltage measurement circuits; obtaining multiple initial state-of-charge parameters
of the battery packs through a microcontroller according to the open circuit voltage
parameters and the temperature parameter; obtaining a current parameter of the battery
packs through a current sampling circuit; and respectively calculating multiple present
battery powers of the battery packs through the microcontroller according to the initial
state-of-charge parameters, the temperature parameter, and the current parameter.
[0007] Based on the above, the battery management system and the battery management method
of the disclosure can accurately estimate the respective initial state of charge of
the battery packs at the present battery temperature as the battery temperature changes,
so that the present battery powers of the battery packs can be precisely calculated.
In addition, the battery management system and the battery management method of the
disclosure can keep updating the present battery powers of the battery packs to effectively
achieve relevant battery protection mechanisms.
[0008] To make the aforementioned more comprehensible, several embodiments accompanied with
drawings are described in detail as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
FIG. 1 is a schematic view of a battery management system according to an embodiment
of the disclosure.
FIG. 2 is a flow chart of a battery management method according to an embodiment of
the disclosure.
FIG. 3 is a relationship graph of a state of charge and an open circuit voltage according
to an embodiment of the disclosure.
FIG. 4 is a relationship graph of a state of charge and a direct current impedance
according to an embodiment of the disclosure.
FIG. 5 is a schematic view of a battery management system according to another embodiment
of the disclosure.
FIG. 6A, FIG. 6B, and FIG. 6C are flow charts of a battery management method according
to another embodiment of the disclosure.
DESCRIPTION OF THE EMBODIMENTS
[0010] To provide a further understanding of the content of the disclosure, the following
embodiments are used as examples based on which the disclosure may be realized. In
addition, wherever possible, elements/components/steps with the same reference numeral
in the drawings and embodiments represent the same or similar components.
[0011] FIG. 1 is a schematic view of a battery management system according to an embodiment
of the disclosure. Referring to FIG. 1, a battery management system 100 includes a
microcontroller 110, multiple voltage measurement circuits 120_1 to 120_N, a temperature
sampling circuit 130, a current sampling circuit 140, and a protection circuit 150,
where N is a positive integer. The battery management system 100 may be disposed in
a battery module 10 and may be coupled to (or may be electrically connected to) multiple
battery packs 200_1 to 200_N to manage a battery state of the battery packs 200_1~200_N.
In the embodiment, the microcontroller 110 is coupled to the voltage measurement circuits
120_1 to 120_N, the temperature sampling circuit 130, the current sampling circuit
140, and the protection circuit 150. The battery management system 100 is electrically
connected between a load positive electrode 101 and a battery positive electrode 201
through a power line 103, and is electrically connected between a load negative electrode
102 and a battery negative electrode 202 through a power line 104. Besides, the battery
packs 200_1 to 200_N may be coupled between the battery positive electrode 201 and
the battery negative electrode 202. In the embodiment, the battery packs 200_1 to
200_N may respectively include multiple aluminum-ion batteries connected in series,
but the disclosure is not limited thereto. In an embodiment, the battery packs 200_1
to 200_N may respectively include, but are not limited to, multiple aluminum capacitances
connected in series, or various aluminum energy storage devices such as solid or liquid
(electrolytic) capacitors, batteries, or supercapacitors made from the aluminum material.
The battery management system and the battery management method provided in each of
the embodiments of the disclosure may be applicable to various aluminum energy storage
devices. Even in another embodiment, the battery packs 200_1 to 200_N may be respectively
storage batteries or capacitors made from other materials.
[0012] In the embodiment, the voltage measurement circuits 120_1 to 120_N are respectively
coupled to the battery packs 200_1 to 200_N one by one to respectively perform voltage
measurements on the battery packs 200_1 to 200_N. The temperature sampling circuit
130 may be disposed on or connected to a periphery of the adjacent battery packs 200_1
to 200_N or battery components to effectively sense a present battery temperature
of the battery packs 200_1 to 200_N. The current sampling circuit 140 may be coupled
to the power line 104 and may measure a present current parameter of the battery packs
200_1 to 200_N. In the embodiment, the current sampling circuit 140 may have a function
of bidirectional current measurement. In particular, the current sampling circuit
140 may be adapted to the characteristics of an aluminum-ion battery (or other aluminum
energy storage devices, such as solid or liquid (electrolytic) capacitors, batteries,
or supercapacitors made from the aluminum material) such as a high coulombic efficiency
and an instantaneous high-power output. The protection circuit 150 may be coupled
to the power line 103, and the microcontroller 110 may determine whether the power
line 103 is conductive through controlling the protection circuit 150 to control whether
the battery packs 200_1 to 200_N are to be charged or discharged.
[0013] FIG. 2 is a flow chart of a battery management method according to an embodiment
of the disclosure. Referring to FIG. 1 and FIG. 2, the battery management system 100
may perform the following Steps S210 to S250 to effectively estimate battery powers
of the battery packs 200_1 to 200_N. In Step S210, the microcontroller 110 may obtain
a temperature parameter (a present temperature) of the battery packs 200_1 to 200_N
through the temperature sampling circuit 130. In Step S220, the microcontroller 110
may obtain multiple open circuit voltage (OCV) parameters (open circuit voltages at
the present temperature) of the battery packs 200_1 to 200_N through the voltage measurement
circuits 120_1 to 120_N. In Step S230, the microcontroller 110 may obtain multiple
initial state-of-charge (SOC) parameters of the battery packs 200_1 to 200_N according
to the open circuit voltage parameters and the temperature parameter.
[0014] Referring to FIG. 3 together with FIG. 1 and FIG. 2, FIG. 3 is a relationship graph
of an initial state of charge and an open circuit voltage according to an embodiment
of the disclosure. For example, the relationship between the state of charge and the
open circuit voltage of the battery packs 200_1 to 200_N may be non-linear due to
different battery temperatures. The battery management system 100 may be pre-built
in with battery parameter information (for example, stored in a storage unit of the
battery management system 100 in a form of a look-up table) of the battery packs 200_1
to 200_N corresponding to the different temperatures as shown in FIG. 3. FIG. 3 may
include relation curves 301 to 304 corresponding to the open circuit voltage and the
state of charge, where the relation curves 301 to 304 may, for example, respectively
correspond to temperatures of 25°C, 40°C, 60°C, and 80°C. Supposing that the present
temperature of the battery packs 200_1 to 200_N which may be obtained by the microcontroller
110 through the temperature sampling circuit 130 is 40°C, and the open circuit voltage
of a certain battery pack which may be obtained by the microcontroller 110 through
a certain voltage measurement circuit is 1.8 volts, the microcontroller 110 may determine
the initial state of charge of the certain battery pack as 40% through the relation
curve 302 in FIG. 3. In other words, the microcontroller 110 may respectively obtain
the corresponding initial state of charge according to the respective open circuit
voltage of the battery packs 200_1~200_N. Therefore, the microcontroller 110 may accurately
estimate the respective initial state of charge of the battery packs 200_1 to 200_N
according to the open circuit voltage parameters changing with temperatures and the
temperature parameter.
[0015] In Step S240, the microcontroller 110 may obtain a current parameter of the battery
packs 200_1 to 200_N through the current sampling circuit 140. In Step S250, the microcontroller
110 may respectively calculate multiple present battery powers (i.e., a present state
of charge) of the battery packs 200_1 to 200_N through the Coulomb counting method
according to the initial state-of-charge parameters, the temperature parameter, and
the current parameter. In this regard, referring to FIG. 4 altogether, FIG. 4 is a
relationship graph of a state of charge and a direct current impedance according to
an embodiment of the disclosure. For example, the relationship between the state of
charge and the direct current impedance of the battery packs 200_1 to 200_N may be
non-linear due to different battery temperatures. The battery management system 100
may be pre-built in with battery parameter information (for example, stored in a storage
unit of the battery management system 100 in a form of a look-up table) of the battery
packs 200_1 to 200_N corresponding to the different temperatures as shown in FIG.
4. FIG. 4 may include relation curves 401 to 404 corresponding to the direct current
impedance and the state of charge, where the relation curves 401 to 404 may, for example,
respectively correspond to temperatures of 25°C, 40°C, 60°C, and 80°C. Supposing that
the present temperature of the battery packs 200_1 to 200_N which may be obtained
by the microcontroller 110 through the temperature sampling circuit 130 is 40°C, the
microcontroller 110 may determine the direct current impedance of a certain battery
pack as 0.0115 ohm according to the present temperature (40°C) and the initial state
of charge (40%) of the certain battery pack previously obtained through the relation
curve 402 in FIG. 4. In other words, the microcontroller 110 may respectively obtain
the corresponding direct current impedance according to the respective initial state
of charge of the battery packs 200_1 to 200_N. Therefore, the battery management system
100 in the embodiment may accurately estimate the respective present battery powers
(i.e., the present state of charge) of the battery packs 200_1 to 200_N according
to the initial state-of-charge parameters changing with temperatures and the direct
current impedance.
[0016] Further specifically, when the microcontroller 110 obtains another temperature parameter
of a next timepoint through the temperature sampling circuit 130 and the another temperature
parameter is different from the temperature parameter of the previous timepoint, the
microcontroller 110 may also update the initial state-of-charge parameters of the
battery packs 200_1 to 200_N according to another multiple open circuit voltage parameters
corresponding to the another temperature parameter and another temperature parameter.
Also, the microcontroller 110 may recalculate the present battery powers of the battery
packs 200_1 to 200_N according to the updated initial state-of-charge parameters.
Therefore, the battery management system 100 in the embodiment may instantaneously
revise the initial state-of-charge parameters as temperature changes over time to
keep accurately estimating the respective present battery powers of the battery packs
200_1 to 200_N.
[0017] It is worth noting that the battery packs 200_1 to 200_N in the embodiment may obtain
battery discharge parameters such as a pulse discharge internal resistance, a pulse
charging internal resistance, and a battery total internal resistance under a predetermined
depth of discharge (DOD) through the calculation of Ohm's law via a hybrid pulse power
characterization test (HPPC) under different temperature conditions in advance, and
may utilize the least squares method to fit experimental data. Then, various battery
performance data parameters such as an Ohm's internal resistance, a polarized resistor
capacitor, and the open circuit voltage may be obtained by feeding curve fitting parameters
of each stage of HPPC into a curve fitting algorithm. In this regard, a set of mathematical
state-prediction model applicable to the aluminum-ion battery (or other aluminum energy
storage devices, such as solid or liquid (electrolytic) capacitors, batteries, or
supercapacitors made from aluminum material) at the different temperatures may be
constructed in the embodiment, and the state of charge of the battery may be precisely
predicted by utilizing a matrix estimation manner to estimate a parameter result for
observing the changing situation of the state of charge of the battery.
[0018] Further specifically, the state of charge of the battery in the embodiment may be
estimated based on, for example, the open-circuit voltage method and the Coulomb counting
method, and the prediction and correction for the state of charge are to be performed
accordingly. In this regard, in the process of estimating the state of charge of the
battery, a state-of-charge model prediction matrix may be configured to estimate the
state of charge of the battery in the embodiment. Moreover, through monitoring the
battery voltages, the currents, and the temperatures, the state of charge is to be
estimated according to the battery at different discharging temperatures, currents,
and voltages. The state matrix of the state of charge may take the state of charge
of the battery and a potential difference of the battery as state variable factors
for prediction and correction, and the state-of-charge factors may be obtained by
a non-linear systemic discreteness of the battery and a linearized parameter. Therefore,
a battery equivalence model, constructed by relevant battery data generated by the
HPPC, with an estimation process of the matrix estimation method may be configured
to estimate the state of charge of the battery in the embodiment.
[0019] In addition, the battery equivalence model may be established by battery characteristics
of different temperatures. The battery equivalence model may be, for example, a two-phase
RC equivalent circuit model, but the disclosure is not limited thereto. It is worth
noting that the establishment of the battery equivalence model in the embodiment may
further take the influence of an electrochemical corrosion polarization and an electrolytic
concentration polarization into consideration.
[0020] FIG. 5 is a schematic view of a battery management system according to another embodiment
of the disclosure. Referring to FIG. 5, a battery management system 500 includes a
microcontroller 510, multiple voltage measurement circuits 520_1 to 520_N, a temperature
sampling circuit 530, a current sampling circuit 540, a protection circuit 550, multiple
balance circuits 560_1 to 560_N, and a voltage converter 570. The battery management
system 500 may be disposed in a battery module 50 and may be coupled to (electrically
connected to) multiple battery packs 600_1 to 600_N to manage a battery state of the
battery packs 600_1 to 600_N. In the embodiment, the microcontroller 510 is coupled
to the voltage measurement circuits 520_1 to 520_N, the temperature sampling circuit
530, a sense resistor 541, the protection circuit 550, the balance circuits 560_1
to 560_N, and the voltage converter 570. The battery management system 500 is electrically
connected between a load positive electrode 501 and a battery positive electrode 601
by a power line 503, and is electrically connected between a load negative electrode
502 and a battery negative electrode 602 by a power line 504. Besides, the battery
packs 600_1 to 600_N may be coupled between the battery positive electrode 601 and
the battery negative electrode 602. In the embodiment, the battery packs 600_1 to
600_N may respectively include multiple batteries C1_1 to CN_M connected in series,
where N and M are positive integers, and the batteries C1_1 to CN_M are respectively
single cells.
[0021] In the embodiment, the microcontroller 510 of the battery management system 500 may
adopt a serial peripheral interface (SPI) to achieve a communication with the voltage
measurement circuits 520_1 to 520_N and a load device coupled to the load positive
electrode 501 and the load negative electrode 502. Also, the microcontroller 510 of
the battery management system 500 may be connected to an external computer equipment
through a universal asynchronous receiver/transmitter (UART) to enable the external
computer equipment to record a firmware into the microcontroller 510. Besides, the
external computer equipment may output instantaneous battery power information to
a human machine interface through the UART to achieve a display and/or a recording
function of the battery information. Nonetheless, the communication interface that
may be adopted by the battery management system 500 in the disclosure is not limited
to the above. In another embodiment, for example, an inter-integrated circuit (I2C),
a controller area network (CAN), or other types of the communication interfaces may
be adopted to achieve the connection interface or an outward connection interface
between internal units of the battery management system 500.
[0022] In the embodiment, the voltage measurement circuits 520_1 to 520_N are respectively
coupled to the battery packs 600_1 to 600_N one by one. The voltage measurement circuits
520_1 to 520_N may be respectively an analog front end (AFE) unit. The voltage measurement
circuits 520_1 to 520_N may respectively include a battery monitor and a signal capturing
unit. The respective signal capturing unit of the voltage measurement circuits 520_1
to 520_N may instantaneously capture multiple voltage signals of the battery packs
600_1 to 600_N, and the voltage parameters of the voltage signals may be monitored
through the battery monitor to respectively judge whether the battery packs 600_1~600_N
have occurred an overvoltage event or a low voltage event. The voltage measurement
circuits 520_1 to 520_N may, for example, respectively detect 12 single cells connect
in series (i.e., M=12). Furthermore, the voltage measurement circuits 520_1 to 520_N
may be isolated from each other by a micro-transformer and may be connected to each
other by a daisy chain. In this regard, the number of the circuits which may be stacked
by the voltage measurement circuits 520_1 to 520_N may be, for example, 10 (i.e.,
N=10). In other words, the maximum number of the batteries managed under the framework
may reach 120 units of series, and, for example, a wide range of 0 to 5 volts (V)
for a voltage measurement function of a cell terminal may be provided.
[0023] In the embodiment, the voltage measurement circuits 520_1 to 520_N may respectively
include a SPI module and an isolated (iso) SPI module. The voltage measurement circuits
520_1 to 520_N may be respectively connected to the microcontroller 510 through the
individual SPI module, and the voltage measurement circuits 520_1 to 520_N may further
be respectively connected to each other through the individual isolated (iso) SPI
module to achieve a synchronous control function (such as a battery balance control).
In the embodiment, the voltage measurement circuits 520_1 to 520_N may further respectively
include a random access memory register (RAM register) configured to store related
voltage sensing results or related control commands. In the embodiment, the balance
circuits 560_1 to 560_N are respectively coupled to the battery packs 600_1 to 600_N
one by one. The microcontroller 510 may include a battery balance control module and
may receive the voltage measurement results of the battery packs 600_1 to 600_N provided
by the voltage measurement circuits 520_1 to 520_N to judge whether the balance circuits
560_1 to 560_N are configured to balance battery powers of the battery packs 600_1
to 600_N.
[0024] In the embodiment, the current sampling circuit 540 may include the sense resistor
541 and a sampling circuit 542. The sense resistor 541 may be coupled to the power
line 504 in series to enable the sampling circuit 542 to calculate the current parameter
flowing through the power line 504 through sampling a voltage change on the sense
resistor 541. However, in another embodiment, the current sampling circuit 540 may
also be implemented by a Hall element. In the embodiment, the microcontroller 510
may include a system on a chip (SOC) counter and may receive current measurement results
of the battery packs 600_1 to 600_N provided by the sampling circuit 542 to calculate
the battery powers of the battery packs 600_1 to 600_N.
[0025] In the embodiment, the protection circuit 550 may include switching transistors 551
and 552 and diodes 553 and 554. The switching transistors 551 and 552 may be respectively
a p-type metal oxide semiconductor field effect transistor (MOSFET), but the disclosure
is not limited thereto. A first terminal of the switching transistor 551 is coupled
to a battery positive electrode 601 and a negative pole of the diode 553, and a second
terminal of the switching transistor 551 is coupled to a first terminal of the switching
transistor 552, a positive pole of the diode 553, and a positive pole of the diode
554. The first terminal of the switching transistor 552 is coupled to the positive
pole of the diode 553 and the positive pole of the diode 554, and a second terminal
of the switching transistor 552 is coupled to the load positive electrode 501 and
a negative pole of the diode 554.
[0026] In the embodiment, when the battery packs 600_1 to 600_N are in a normal state, the
microcontroller 510 may control the switching transistor 551 and the switching transistor
552 to be in a conduction state to enable the switching transistor 551 and the switching
transistor 552 to form a discharge loop and/or a charge loop. In this way, a discharge
current received by the battery positive electrode 601 from the battery packs 600_1
to 600_N may be provided to the load positive electrode 501 through the switching
transistor 551 and the switching transistor 552, that is, the battery packs 600_1
to 600_N may be allowed to discharge to the load device. The load positive electrode
501 may provide a charge current to the battery positive electrode 601 through the
switching transistor 551 and the switching transistor 552, that is, the load device
may be allowed to charge the battery packs 600_1 to 600_N.
[0027] In the embodiment, when the battery packs 600_1 to 600_N are in an over-discharge
state due to an abnormal discharge, the microcontroller 510 may control the switching
transistor 551 to be in a non-conduction state to close the discharge loop. At this
moment, the microcontroller 510 may control the switching transistor 552 to maintain
the conduction state. In this way, the battery packs 600_1 to 600_N may not be discharged
to the load device, but the load device may be allowed to charge the battery packs
600_1 to 600_N. The charge current received by the load positive electrode 501 from
the load device may be provided to the battery positive electrode 601 through the
switching transistor 552 and the diode 553 to charge the battery packs 600_1 to 600_N.
Until when the battery voltages are raised to a low voltage resetting value, the microcontroller
510 may control the switching transistor 551 to return to the conduction state to
enable the battery packs 600_1 to 600_N to discharge to the load device again.
[0028] In the embodiment, when the battery packs 600_1 to 600_N are in an over-charge state
due to the occurrence of the over charge, the microcontroller 510 may control the
switching transistor 552 to be in the non-conduction state to close the charge loop.
At this moment, the microcontroller 510 may control the switching transistor 551 to
maintain the conduction state. In this way, the load device does not charge the battery
packs 600_1 to 600_N, but the battery packs 600_1 to 600_N may be allowed to discharge
to the load device. The discharge current of the battery packs 600_1 to 600_N may
be provided to the load positive electrode 501 via the battery positive electrode
601, the switching transistor 551, and the diode 554 for discharge. Until when the
battery voltages decline to a high voltage resetting value, the microcontroller 510
may control the switching transistor 552 to return to the conduction state to enable
the load device to charge the battery packs 600_1 to 600_N again.
[0029] In the embodiment, the microcontroller 510 may include a protection control circuit
and a transistor driver. The transistor driver may output two control signals to respective
control terminals of the switching transistor 551 and the switching transistor 552.
In this regard, the protection control circuit may judge whether an abnormal event
occurs according to the voltage measurement results, a temperature measurement result,
and the current measurement result of the battery packs 600_1 to 600_N respectively
provided by the voltage measurement circuits 520_1 to 520_N, the temperature sampling
circuit 530, and the sampling circuit 542 to conduct or close the loop through operating
the switching transistor 551 and the switching transistor 552 by the transistor driver.
[0030] In the embodiment, the voltage converter 570 may be a direct current to direct current
converter (DC to DC converter) to provide a direct-current voltage conversion function.
The voltage converter 570 is coupled to the power line 503 and may obtain direct-current
voltage signals provided by the battery packs 600_1 to 600_N. The voltage converter
570 may convert the direct-current voltage signals into power voltages that may drive
the microcontroller 510 and may provide the power voltages to the microcontroller
510. Moreover, in another embodiment, the microcontroller 510 may further include,
for example, a SPI interface module and a pre-charge module. The microcontroller 510
may be connected to other functional circuits and an external load device through
the SPI interface module. The microcontroller 510 may pre-charge the battery packs
600_1 to 600_N through the pre-charge module.
[0031] FIG. 6A, FIG. 6B, and FIG. 6C are flow charts of a battery management method according
to another embodiment of the disclosure. Referring to FIG. 5, FIG. 6A, FIG. 6B, and
FIG. 6C, the battery management system 500 may perform the following Steps S601 to
S643 to achieve the battery management and protection functions. It is worth noting
that the microcontroller 510 may record data with multiple flags to indicate present
operating state of the battery and may update the present battery state to the load
device. The load device may determine to perform corresponding operation on the battery
packs 600_1 to 600_N according to the present battery state, and when the corresponding
operation is completed, the load device (or the microcontroller 510 automatically
updates) may update the data with the flags recorded by the microcontroller 510.
[0032] In Step S601, the microcontroller 510 initializes system settings to load related
control commands and protection parameters. In Step S602, the microcontroller 510
performs the measurement of the initial state of charge to obtain the respective initial
state-of-charge parameters of the battery packs 600_1 to 600_N according to the respective
open circuit voltage parameters of the battery packs 600_1 to 600_N. In Step S603,
the microcontroller 510 may obtain a temperature parameter of the battery packs 600_1~600_N
through the temperature sampling circuit 530. In Step S604, the microcontroller 510
may obtain the voltage parameters of the battery packs 600_1 to 600_N through the
voltage measurement circuits 520_1 to 520_N. In Step S605, the microcontroller 510
may obtain a current parameter of the battery packs 600_1 to 600_N through the current
sampling circuit 540. In Step S606, the microcontroller 510 may judge a current direction
on the power line 504 through the current sampling circuit 540 to judge whether the
present operating state of the battery packs 600_1 to 600_N is a charge mode, a discharge
mode, or a static mode. In Step S607, the microcontroller 510 may calculate present
battery powers of the battery packs 600_1 to 600_N according to the temperature parameter,
the voltage parameters, and the current parameter. In this regard, the calculation
method of the present battery powers of the battery packs 600_1 to 600_N may be referred
to the description of the above-mentioned embodiments in FIG. 1 to FIG. 4, so there
is no repetition here.
[0033] In Step S608, the microcontroller 510 may judge whether an abnormal temperature occurs
through the temperature sampling circuit 530. If the abnormal temperature occurs,
then in Step S609, the microcontroller 510 may set a temperature flag as abnormal.
In Step S610, the microcontroller 510 may operate the protection circuit 550 to break
the charge/discharge loop. In Step S618, the microcontroller 510 may automatically
check the system or remind a user to check the battery module 50 by means. In Step
S611, the microcontroller 510 may send the present battery state to the load device
to enable the load device to perform the corresponding operation according to the
present battery state. Next, the microcontroller 510 may perform Step S603 and may
recursively update the present battery powers of the battery packs 600_1 to 600_N
via Steps S603-S607.
[0034] If the abnormal temperature does not occur, in Step S612, the microcontroller 510
may judge whether an overcurrent event has occurred through the current sampling circuit
540. If the overcurrent event has occurred, then in Step S613, the microcontroller
510 judges the current direction. If the present operation of the battery packs 600_1
to 600_N is in the charge mode, then in Step S614, the microcontroller 510 may set
a charge flag as an abnormal current. In Step S615, the microcontroller 510 may operate
the protection circuit 550 to break the charge loop. Relatively, if the present operation
of the battery packs 600_1 to 600_N is in the discharge mode, then in Step S616, the
microcontroller 510 may set a discharge flag as the abnormal current. In Step S617,
the microcontroller 510 may operate the protection circuit 550 to break the discharge
loop. Next, the microcontroller 510 may perform S618, S611, and S603~S607 to recursively
update the present battery powers of the battery packs 600_1 to 600_N.
[0035] If the overcurrent event has not occurred, in Step S619, the microcontroller 510
may judge whether the overvoltage event has occurred through the voltage measurement
circuits 520_1 to 520_N. If the overvoltage event has occurred in at least one of
the present battery packs 600_1 to 600_N, then in Step S620, the microcontroller 510
may set the charge flag as an abnormal voltage. In Step S621, the microcontroller
510 may operate the protection circuit 550 to break the charge loop. In Step S622,
the microcontroller 510 may operate at least one of the corresponding balance circuits
560_1 to 560_N to perform a battery balance. Next, the controller 510 may perform
S611, S603~S607 to notify the load device to perform the corresponding operation and
may recursively update the present battery powers of the battery packs 600_1 to 600_N.
[0036] If the overvoltage event has not occurred, in Step S623, the microcontroller 510
may judge whether the low voltage event has occurred through the voltage measurement
circuits 520_1 to 520_N. If the low voltage event occurs in the at least one of the
present battery packs 600_1 to 600_N, then in Step S624, the microcontroller 510 may
set the discharge flag as the abnormal voltage. In Step S625, the microcontroller
510 may operate the protection circuit 550 to break the discharge loop. In Step S626,
the microcontroller 510 may correct the initial state-of-charge parameters due to
an excessive discharge of the battery packs 600_1 to 600_N. Next, the controller 510
may perform S611, S603~S607 to notify the load device to perform the corresponding
operation and may recursively update the present battery powers of the battery packs
600_1 to 600_N.
[0037] If the low voltage event has not occurred, in Step S627 and Step S628, the microcontroller
510 may judge whether the charge reaches a cut-off voltage and/or a cut-off current
through the voltage measurement circuits 520_1 to 520_N and the current sampling circuit
540. If the charge reaches the cut-off voltage and the cut-off current, then in Step
S629, the microcontroller 510 may set the charge flag as a completion of the charge.
In Step S630, the microcontroller 510 may operate the protection circuit 550 to break
the charge loop. Next, the controller 510 may perform S611, S603~S607 to notify the
load device to perform the corresponding operation and may recursively update the
present battery powers of the battery packs 600_1 to 600_N.
[0038] If the charge does not reach the cut-off voltage or the cut-off current, in Step
S631, the microcontroller 510 may judge whether the battery packs 600_1 to 600_N are
left static for a predetermined time duration (for example, 12 hours). If the battery
packs 600_1 to 600_N are left static for the predetermined time duration, in Step
S632, the microcontroller 510 may correct the initial state-of-charge parameters.
Next, the controller 510 may perform S611, S603~S607 to notify the load device to
perform the corresponding operation and may recursively update the present battery
powers of the battery packs 600_1 to 600_N.
[0039] If the battery packs 600_1 to 600_N are not left static for the predetermined time
duration, in Step S633, the microcontroller 510 may judge whether the temperature
of the battery packs 600_1 to 600_N reaches a temperature resetting value through
the temperature sampling circuit 530. If the temperature of the battery packs 600_1
to 600_N reaches the temperature resetting value, then the microcontroller 510 may
set the temperature flag as a normal temperature. In Step S635, the microcontroller
510 may judge whether a current flag is abnormal. If so, the microcontroller 510 may
perform S611, S603~S607 to notify the load device to perform the corresponding operation
and may recursively update the present battery powers of the battery packs 600_1 to
600_N. If the temperature of the battery packs 600_1 to 600_N does not reach the temperature
resetting value, then the microcontroller 510 may perform S611, S603~S607 to notify
the load device to perform the corresponding operation and may recursively update
the present battery powers of the battery packs 600_1 to 600_N.
[0040] If the current flag is not abnormal, then in Step S636, the microcontroller 510 may
judge whether the battery balance is to be performed. If the battery packs 600_1 to
600_N are performing the battery balance, then in Step S637, the microcontroller 510
may judge whether the voltages of the battery packs 600_1 to 600_N reach a high voltage
resetting value through the voltage measurement circuits 520_1 to 520_N. If the voltages
of the battery packs 600_1 to 600_N reach the high voltage resetting value, then in
Step S638, the microcontroller 510 may set the charge flag as a normal voltage. In
Step S639, the microcontroller 510 may end the battery balance operation. In Step
S643, the microcontroller 510 may operate the protection circuit 550 to reset the
charge loop (may continue to charge). Next, the microcontroller 510 may perform S611,
S603-S607 to notify the load device to perform the corresponding operation and may
recursively update the present battery powers of the battery packs 600_1 to 600_N.
[0041] If the voltages of the battery packs 600_1 to 600_N do not reach the high voltage
resetting value, then in Step S640, the microcontroller 510 may judge whether the
voltages of the battery packs 600_1 to 600_N reach a low voltage resetting value through
the voltage measurement circuits 520_1 to 520_N. If the voltages of the battery packs
600_1 to 600_N reach the low voltage resetting value, then in Step S641, the microcontroller
510 may set the discharge flag as the normal voltage. In Step S642, the microcontroller
510 may operate the protection circuit 550 to reset the discharge loop (may continue
to discharge). If the voltages of the battery packs 600_1 to 600_N do not reach the
low voltage resetting value, the microcontroller 510 may perform S611, S603~S607 to
notify the load device to perform the corresponding operation and may recursively
update the present battery powers of the battery packs 600_1~600_N.
[0042] In summary of the above, the battery management system and the battery management
method of the disclosure can instantaneously monitor the voltage parameters, the current
parameter, and the temperature parameter of the battery packs to achieve protection
mechanisms for an overvoltage, an overcurrent, or an overtemperature. The battery
management system and the battery management method of the disclosure can consider
the influence of the temperature on the state of charge of the battery and thus can
automatically update the initial state of charge of the battery packs to accurately
estimate the present battery powers of the battery packs. In addition, the battery
management system of the disclosure can achieve a stackable modular design to be adapted
to apply to diverse fields and diverse storage batteries, and the battery management
system of the disclosure can further achieve the battery balance function. Therefore,
the battery management system and the battery management method of the disclosure
can further have an effect of extending lifetime of the storage batteries.
1. A battery management system (100, 500), comprising:
a temperature sampling circuit (130, 530), configured to obtain a temperature parameter
of a plurality of battery packs (200_1 to 200_N, 600_1 to 600_N);
a plurality of voltage measurement circuits (120_1 to 120_N, 520_1 to 520_N), respectively
coupled to the battery packs (200_1 to 200_N, 600_1 to 600_N) and configured to obtain
a plurality of open circuit voltage parameters of the battery packs (200_1 to 200_N,
600_1 to 600_N);
a current sampling circuit (140, 540), coupled to the battery packs (200_1 to 200_N,
600_1 to 600_N) and configured to obtain a current parameter of the battery packs
(200_1 to 200_N, 600_1 to 600_N); and
a microcontroller (110, 510), coupled to the voltage measurement circuits (120_1 to
120_N, 520_1 to 520_N), the current sampling circuit (140, 540), and the temperature
sampling circuit (130, 530),
wherein the microcontroller (110, 510) obtains a plurality of initial state-of-charge
parameters of the battery packs (200_1 to 200_N, 600_1 to 600_N) according to the
open circuit voltage parameters and the temperature parameter and respectively calculates
a plurality of present battery powers of the battery packs (200_1 to 200_N, 600_1
to 600_N) according to the initial state-of-charge parameters, the temperature parameter,
and the current parameter.
2. The battery management system (100, 500) according to claim 1, wherein the microcontroller
(110, 510) uses the open circuit voltage parameters and the temperature parameter
to search a battery parameter table to obtain the initial state-of-charge parameters,
wherein the battery packs (200_1 to 200_N, 600_1 to 600_N) construct a corresponding
battery equivalence model via a hybrid pulse power characterization test in advance,
and the battery parameter table is established by inputting a plurality of battery
model parameters corresponding to different temperatures into the battery equivalence
model.
3. The battery management system (100, 500) according to claim 1, wherein when the temperature
sampling circuit (130, 530) obtains an another temperature parameter of a next timepoint,
the microcontroller (110, 510) updates the initial state-of-charge parameters of the
battery packs (200_1 to 200_N, 600_1 to 600_N) according to the open circuit voltage
parameters and the another temperature parameter and recalculates the present battery
powers of the battery packs (200_1 to 200_N, 600_1 to 600_N) according to the updated
initial state-of-charge parameters.
4. The battery management system (100, 500) according to claim 1, further comprising:
a protection circuit (150, 550), coupled to the battery packs (200_1 to 200_N, 600_1
to 600_N) and the microcontroller (110, 510),
wherein when the microcontroller (110, 510) judges that the battery packs (200_1 to
200_N, 600_1 to 600_N) are in an abnormal temperature state according to the temperature
parameter, the microcontroller (110, 510) operates the protection circuit (150, 550)
to break a charge/discharge loop of the battery packs (200_1 to 200_N, 600_1 to 600_N).
5. The battery management system (100, 500) according to claim 4, wherein when the microcontroller
(110, 510) judges that the battery packs (200_1 to 200_N, 600_1 to 600_N) are in an
overcurrent state according to the current parameter, the microcontroller (110, 510)
judges that the battery packs (200_1 to 200_N, 600_1 to 600_N) are performing a charge
operation or a discharge operation according to the current parameter, and the microcontroller
(110, 510) operates the protection circuit (150, 550) to break the charge loop or
the discharge loop of the battery packs (200_1 to 200_N, 600_1 to 600_N).
6. The battery management system (100, 500) according to claim 4, further comprising:
a plurality of balance circuits (560_1 to 560_N), respectively coupled to the battery
packs (200_1 to 200_N, 600_1 to 600_N) and the microcontroller (110, 510),
wherein the microcontroller (110, 510) obtains a plurality of voltage parameters of
the battery packs (200_1 to 200_N, 600_1 to 600_N) through the voltage measurement
circuits (120_1 to 120_N, 520_1 to 520_N), when the microcontroller (110, 510) judges
that at least one of the battery packs (200_1 to 200_N, 600_1 to 600_N) is in an overvoltage
state according to the voltage parameters, the microcontroller (110, 510) operates
the protection circuit (150, 550) to break the charge loop of the battery packs (200_1
to 200_N, 600_1 to 600_N), and the microcontroller (110, 510) operates at least one
of the corresponding balance circuits (560_1 to 560_N) to perform a battery balance
operation on the at least one of the battery packs (200_1 to 200_N, 600_1 to 600_N).
7. The battery management system (100, 500) according to claim 4, wherein the microcontroller
(110, 510) obtains a plurality of voltage parameters of the battery packs (200_1 to
200_N, 600_1 to 600_N) through the voltage measurement circuits (120_1 to 120_N, 520_1
to 520_N), when the microcontroller (110, 510) judges that at least one of the battery
packs (200_1 to 200_N, 600_1 to 600_N) is in a low voltage state according to the
voltage parameters, the microcontroller (110, 510) operates the protection circuit
(150, 550) to break the discharge loop of the battery packs (200_1 to 200_N, 600_1
to 600_N), and the microcontroller (110, 510) corrects the initial state-of-charge
parameters corresponding to the at least one of the battery packs (200_1 to 200_N,
600_1 to 600_N).
8. The battery management system (100, 500) according to claim 4, wherein the microcontroller
(110, 510) obtains a plurality of present voltage parameters of the battery packs
(200_1 to 200_N, 600_1 to 600_N) through the voltage measurement circuits (120_1 to
120_N, 520_1 to 520_N), and the microcontroller (110, 510) obtains a present current
parameter of the battery packs (200_1 to 200_N, 600_1 to 600_N) through the current
sampling circuit (140, 540), when the microcontroller (110, 510) judges that the present
voltage parameters reach a cut-off voltage and the present current parameter reaches
a cut-off current, the microcontroller (110, 510) operates the protection circuit
(150, 550) to break the charge loop of the battery packs (200_1 to 200_N, 600_1 to
600_N) and corrects the initial state-of-charge parameters corresponding to the battery
packs (200_1 to 200_N, 600_1 to 600_N).
9. The battery management system (100, 500) according to claim 1, wherein when the microcontroller
(110, 510) judges that the battery packs (200_1 to 200_N, 600_1 to 600_N) are left
static for a predetermined time duration, the microcontroller (110, 510) corrects
the initial state-of-charge parameters corresponding to the battery packs (200_1 to
200_N, 600_1 to 600_N).
10. The battery management system (100, 500) according to claim 1, wherein the battery
packs (200_1 to 200_N, 600_1 to 600_N) respectively comprise a plurality of aluminum-ion
batteries connected in series.
11. A battery management method, comprising:
obtaining a temperature parameter of a plurality of battery packs (200_1 to 200_N,
600_1 to 600_N) through a temperature sampling circuit (130, 530);
obtaining a plurality of open circuit voltage parameters of the battery packs (200_1
to 200_N, 600_1 to 600_N) through a plurality of voltage measurement circuits (120_1
to 120_N, 520_1 to 520_N);
obtaining a plurality of initial state-of-charge parameters of the battery packs (200_1
to 200_N, 600_1 to 600_N) through a microcontroller (110, 510) according to the open
circuit voltage parameters and the temperature parameter;
obtaining a current parameter of the battery packs (200_1 to 200_N, 600_1 to 600_N)
through a current sampling circuit (140, 540); and
respectively calculating a plurality of present battery powers of the battery packs
(200_1 to 200_N, 600_1 to 600_N) through the microcontroller (110, 510) according
to the initial state-of-charge parameters, the temperature parameter, and the current
parameter.
12. The battery management method according to claim 11, wherein obtaining the open circuit
voltage parameters of the battery packs (200_1 to 200_N, 600_1 to 600_N) comprises:
searching a battery parameter table using the open circuit voltage parameters and
the temperature parameter through the microcontroller (110, 510) to obtain the initial
state-of-charge parameters,
wherein the battery packs (200_1 to 200_N, 600_1 to 600_N) construct a corresponding
battery equivalence model through a hybrid pulse power characterization test in advance,
and the battery parameter table is established by inputting a plurality of battery
model parameters corresponding to different temperatures into the battery equivalence
model.
13. The battery management method according to claim 11, further comprising:
when the temperature sampling circuit (130, 530) obtains an another temperature parameter
of a next timepoint, updating the initial state-of-charge parameters of the battery
packs (200_1 to 200_N, 600_1 to 600_N) through the microcontroller (110, 510) according
to the open circuit voltage parameters and the another temperature parameter; and
recalculating the present battery powers of the battery packs (200_1 to 200_N, 600_1
to 600_N) through the microcontroller (110, 510) according to the updated initial
state-of-charge parameters.
14. The battery management method according to claim 11, further comprising:
when the microcontroller (110, 510) judges that the battery packs (200_1 to 200_N,
600_1 to 600_N) are in an abnormal temperature state according to the temperature
parameter, operating a protection circuit (150, 550) coupled to the battery packs
(200_1 to 200_N, 600_1 to 600_N) through the microcontroller (110, 510) to break a
charge/discharge loop of the battery packs (200_1 to 200_N, 600_1 to 600_N).
15. The battery management method according to claim 14, further comprising:
when the microcontroller (110, 510) judges that the battery packs (200_1 to 200_N,
600_1 to 600_N) are in an overcurrent state according to the current parameter, judging
whether the battery packs (200_1 to 200_N, 600_1 to 600_N) are performing a charge
operation or a discharge operation through the microcontroller (110, 510) according
to the current parameter, and operating the protection circuit (150, 550) to break
the charge loop or the discharge loop of the battery packs (200_1 to 200_N, 600_1
to 600_N).
16. The battery management method according to claim 14, further comprising:
obtaining a plurality of voltage parameters of the battery packs (200_1 to 200_N,
600_1 to 600_N) through the voltage measurement circuits (120_1 to 120_N, 520_1 to
520_N);
when the microcontroller (110, 510) judges that at least one of the battery packs
(200_1 to 200_N, 600_1 to 600_N) is in an overvoltage state according to the voltage
parameters, operating the protection circuit (150, 550) through the microcontroller
(110, 510) to break the charge loop of the battery packs (200_1 to 200_N, 600_1 to
600_N); and
operating at least one of a plurality of corresponding balance circuits (560_1 to
560_N) coupled to the battery packs (200_1 to 200_N, 600_1 to 600_N) through the microcontroller
(110, 510) to perform a battery balance operation on the at least one of the battery
packs (200_1 to 200_N, 600_1 to 600_N).
17. The battery management method according to claim 14, further comprising:
obtaining a plurality of voltage parameters of the battery packs (200_1 to 200_N,
600_1 to 600_N) through the voltage measurement circuits (120_1 to 120_N, 520_1 to
520_N);
when the microcontroller (110, 510) judges that at least one of the battery packs
(200_1 to 200_N, 600_1 to 600_N) is in a low voltage state according to the voltage
parameters, operating the protection circuit (150, 550) through the microcontroller
(110, 510) to break the discharge loop of the battery packs (200_1 to 200_N, 600_1
to 600_N); and
correcting the initial state-of-charge parameters corresponding to the at least one
of the battery packs (200_1 to 200_N, 600_1 to 600_N) through the microcontroller
(110, 510).
18. The battery management method according to claim 14, further comprising:
obtaining a plurality of present voltage parameters of the battery packs (200_1 to
200_N, 600_1 to 600_N) through the voltage measurement circuits (120_1 to 120_N, 520_1
to 520_N);
obtaining a present current parameter of the battery packs (200_1 to 200_N, 600_1
to 600_N) through the current sampling circuit (140, 540);
when the microcontroller (110, 510) judges that the present voltage parameters reach
a cut-off voltage and the present current parameter reaches a cut-off current, operating
the protection circuit (150, 550) through the microcontroller (110, 510) to break
the charge loop of the battery packs (200_1 to 200_N, 600_1 to 600_N); and
correcting the initial state-of-charge parameters corresponding to the battery packs
(200_1 to 200_N, 600_1 to 600_N) through the microcontroller (110, 510).
19. The battery management method according to claim 11, further comprising:
when the microcontroller (110, 510) judges that the battery packs (200_1 to 200_N,
600_1 to 600_N) are left static for a predetermined time duration, correcting the
initial state-of-charge parameters corresponding to the battery packs (200_1 to 200_N,
600_1 to 600_N) through the microcontroller (110, 510).
20. The battery management method according to claim 11, wherein the battery packs (200_1
to 200_N, 600_1 to 600_N) respectively comprise a plurality of aluminum-ion batteries
connected in series.